The present invention relates to voice mail systems, and in particular to the way in which subscribers to such voice mail systems can be notified that they have new messages.
Voice mail systems (also termed voice messaging systems) attach to the telephone network, often via a PBX, and are used to store messages from incoming calls when the intended recipient is absent or otherwise engaged. The intended recipient (a subscriber) can then listen to their stored messages at some future time. A voice mail system is generally implemented either on special purpose computer hardware, or else on a standard computer workstation equipped with a suitable telephony interface. Such voice mail systems are well-known; one example is the DirectTalkMail system, available from IBM Corporation, which operates in conjunction with the DirectTalk/6000 voice processing system (also available from IBM). Other examples of voice mail systems are described in U.S. Pat. No. 5,136,648 and EPA 0588576.
An important feature of such voice mail systems is their ability to notify subscribers that they have a message waiting. This notification is often performed either by a light on the subscribers telephone handset, or via some audible prompt next time the subscriber tries to dial out.
In recent years various attempts have been made to provide a more unified mail system which can handle both voice messages and computer email messages (such systems are sometimes referred to as multimedia systems). For example, WO87/07801 discloses an integrated system which combines a voice mail system and a computer e-mail system. In this integrated system, the user may designate one mail system (ie voice or computer) as the primary recipient for all messages. For example, if the computer is chosen as the primary recipient, then notifications of both telephone and e-mail incoming messages are provided at a desktop computer. Alternatively it is possible to chose to receive notifications of all messages via the voice mail system. In this latter case, a text to speech system may also be used to allow text (ie e-mail) messages to be accessed over the telephone. Another integrated messaging system is taught in U.S. Pat. No. 5,333,266. Commercially available products which provide integrated or unified messaging include CallXpress3 DeskTop for Windows, available from Applied Voice Technology Incorporated, VMX DeskTop for Windows, available from VMX Incorporated (now part of Octel Communications Corporation), and Intuity from AT&T, described in Computer Reseller News, Nov. 28, 1994, p12.
The typical desktop computer interface of such unified systems provides for much greater and more flexible information interchange between the subscriber and the voice mail system than has hitherto been practicable. Thus the user no longer has to try to remember information and instructions played out from the voice mail system, rather this can be conveniently displayed on the computer screen. Likewise, user input commands to the voice mail system are no longer restricted to the conventional 12 touchtone (DTMF) keys on a telephone keypad, but rather can exploit the whole computer keyboard and full power of the GUI. An additional benefit of a unified mail system of course is that a user may process both voice mail and e-mail in the same session.
Nevertheless, there are problems with developing such computer interfaces for voice mail systems. Thus the big advantage of conventional voice mail systems is that a user can access them from a standard telephone anywhere in the world, because the telephone is both uniform and ubiquitous. By contrast, the computer world is full of heterogeneity; users are often equipped with a variety of computers and operating systems even within a single organisation. In addition, remote access to the voice mail system may be much more difficult via a computer network than through the telephone network.
The above problems can be overcome by providing access to a voice mail system from a WorldWideWeb (WWW) client on the Internet, as described in PCT patent application PCT/GB95/02009. This allows subscribers to access their voice mail from any WWW client that has an Internet connection. In particular, by going to a WWW page representing the voice mail system, and by entering their mailbox number, a subscriber can see how many new and old messages he or she has, and optionally can select a message to listen to.
The above-mentioned PCT application therefore provides a voice mail system which allows subscribers to review and access their messages over the WWW. However, the system described therein does not address message notification over the WWW, other than requiring a user to repeatedly re-load the same page whenever they wish to see if any new messages have arrived (note that because some browsers may cache WWW pages, such repeated re-loading may in fact require the browser to be terminated and re-started).